6h

6H is a designation for a graphite pencil hardness grade. On the pencil hardness scale, the letter H indicates hardness, and higher numbers denote harder leads. 6H is among the harder common grades and produces very light, precise lines with minimal graphite transfer. The scale typically runs from 9B (softest) to 9H (hardest), with HB and F occupying the middle range. Exact formulations vary by manufacturer, but 6H generally uses more clay relative to graphite to achieve the increased hardness.

The primary use for 6H pencils is technical drawing and drafting. They are favored for initial outlines, construction lines, and fine details that should stay unobtrusive in the final drawing. 6H marks are often lighter and easier to control on smooth drafting papers, vellum, or film, and they are less prone to smudging compared with softer grades. Because the lead is very hard and brittle, they require a sharp point and light pressure, and shading or broad tonal work is impractical with this grade.

Availability and context: 6H is common in professional drawing kits but is less prevalent in casual pencils, where mid-range hardness grades such as 2H or HB are more typical. Artists and drafters may use 6H in combination with softer pencils (eg, HB, 2B) to separate line work from shading.